The power transmissions often require a gear member and associating friction device, such as a clutch or brake, to be mounted axially spaced from each other within a housing. The ring gear is positioned along a hub member. This positioning usually occurs with the use of a retainer ring which is fixed in a circumferential groove on a hub following assembly of the ring gear to the hub. Also in such assemblies, a friction device is mounted axially along the hub to which the ring gear is secured and the housing of the friction device quite often must be retained relative to the hub, thus requiring an additional retaining ring.